/Engine/Source/Editor/UnrealEd/Public/Kismet2/BlueprintEditorUtils.h
Looks through the specified blueprint for any references to the specified variable, and renames them accordingly.
static void RenameVariableReferences ( [UBlueprint](API\Runtime\Engine\Engine\UBlueprint) * Blueprint, [UClass](API\Runtime\CoreUObject\UObject\UClass) * VariableClass, const [FName](API\Runtime\Core\UObject\FName) & OldVarName, const [FName](API\Runtime\Core\UObject\FName) & NewVarName )